<html>
  <body>
    <script>
      // 此代码段只有顺序结构
      let input1, input2, sum, num1, num2;
      input1 = prompt("Please enter a number", "0");
      input2 = prompt("Please enter a number", "0");
      num1 = parseInt(input1); //parseInt是一个函数(function) 用来将括号里面的值转换为整数
      num2 = parseInt(input2);
      console.log(num1);
      console.log("num2:" + num2);
      sum = num1 + num2;
      // sum = input1 + input2
      document.writeln("<h1>the sum is " + sum + "</h1>");
    </script>
    <p>
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Eaque libero sunt
      vero corporis fugit? Itaque mollitia fugit ipsum officiis molestiae,
      architecto accusantium dolorem et, quibusdam consequuntur, similique in
      officia! Recusandae!
    </p>
  </body>
</html>
